PURPOSE: To carry out the optical resolution of a mixture of the D- and L- isomers of threo-3-(3,4-methylenedioxyphenyl)serine ester derivative, by using an optically active compound available easily from the antipode of the desired optically active compound, as a resolving agent.
CONSTITUTION: The optically active isomer of the phenylserine derivative of formula I can be prepared by carrying out the optical resolution of a mixture of D-isomer and L-isomer (preferably racemic compound) of the ester derivative of threo-3-(3,4-methylenedioxy-phenyl)serine of formula I (R1 is lower alkyl) using D- or L- threo-N-acyl-3-(3,4-methylenephenyl)serine derivative of formula II (R2 is H or alkyl) as an optical resolution agent, and desalting the obtained carboxylic acid salt of an optically active phenylserine ester derivative.
USE: In intermediate of the compound of formula III useful as a remedy for peripheral orthostatic hypotension, antidepresent, remedy for Parkinson's disease, etc.
MAEJIMA KAORU
NAGATA SHOJI
KOJIMA YOSHIYUKI
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